Let-off mechanism for looms



Dec. 9, 15 24. 1,518,379

E. BARBER LETOFF MECHANISM FOR LOOMS Filed NOV. 22, 1922 2 Sheets-Sheet 1 WITNESS IIVVEIVTOR' ATTORNEY.

E. BARBER Dec, 9, 1924.

LETOFF MECHANISM FOR LOOMS Filed NOV. 22, 1922 2 SheetsSheec 2 m M w than gradual in character.

Patented Dec. 9, 1924.

UNITED STATES ERNEST BARBER,- QF PATERSON, NEW JERSEY.

LET-OFF MEQHANISM FOR LOOMS.

Application filed Iiovember 22, 1922. Serial Ito-602,640..

To all 1071 0172 it may concern:

Be it known that I, ERNEST BARBER, a citizen of the United States, residing at Paterson, in the county of Passaic and State of New Jersey, have invented certain new and useful Improvements in Let-Off Mechanisms for Looms, of which the following is a specification.

This invention relates to mechanism for 1 frictionally controlling the rotation of the beam (as the let-off beam in a loom) from which a war 3 or other sheet is delivered by draft exertec on the sheet. In looms it is common to use a rope or equivalent flexible 13 device wrapped one or more times around the beam and having the end which extends relatively reversely to the free end of the warp provided with a normally pendent weight and the other end either attached to some fixed point or provided with a weight which as the beam is rotated by the pull of the warp contacts with the floor or other stop, thus to relax the rope and permit the beam to rotate relatively to it. It

5 is known that such means is unsuitable for certain purposes, as in the weaving of fine fabrics where it results in imperfections being produced in the weave, such as socalled shyers, which are an irregular spacing of the filling or weft threads due to the letting-off action not being uniform in character, this in turn being due to the advances of the beam relatively to the rope or equivalent being jerky or sudden rather The object of this invention is to provide a let-off mecha' nism in which the movement of the beam under the pull of the warp or other sheet shall be at all times gradual and smooth, all

r tendency of the beam to stick to the braking medium (which is primarily responsible for orkiness in the action) being eliminated.

in the drawings,

.15 Fig. 1 is a side elevation of the improved let-off mechanism;

Fig. 2 is a rear elevation; Fig. 3 is a fragmentary side elevation on a larger scale, partly in section; and Fig. 4 is a fragmentary section on line it-4E, Fig. 3.

A suitable support is afforded by the stand a, which may be a part of a loom frame 6. In the support is journaled the beam 0 having a head 0 grooved peripherally as at c". The warp delivered from the beam is indicated at cl.

The means to exert constrictingpressure on the beam in the present example includes a rope e which is formed with wrappings 6 extending around the beam head 0 and has the forward end thereof connected with the floor by the spring 7 and the other end weighted, as by being connected to a suitably fulcrumed lever g which carries 6 weighting means h. It also includes in the present example a series of bolsters 2' which and the manner of connecting them together will be later described in detail and which serve in such example to support the wrappings of the rope and afford bearings for the rolling pressure-transmitting intermediaries.

The rolling pressuretransmitting intermediaries are in thepresent example rollers j. In such example these roll on the surface of the groove 0 of the beam-head and have hearings. in the bolsters.

Each bolster includes a block which. straddles the periphery of the beam-head c and has inwardly projecting bearing lugs t" in which is suitably held, as by cotter-pins k as shown, a spindle is on which the rollers j are journaled; the block also has outwardly projecting lugs 71 which together form a recessed seat in the bolster adapted to re ceive the wrappings of the rope c, as shown. Each bolster with the rollers journaled therein is connected with two other such bolsters (one on each side thereof), so as to form an no endless flexible system, by links Z. In the example illustrated it is indicated that the blocks may at intervals be omitted, if desired, there being no blocks shown assembled with the alternate spindles 7c.

When the improved mechanism is in use the warp is delivered in a manner devoid of all jerkiness or sudden slippage, and this is so whether by adjustment (as by increas-- ing or decreasing the weight it) the tension 1. and consequently the resistance opposed to the rotation of the beam is made great or little. Moreover, this delivery takes place without erkiness, but in a gradual or eased manner, although each opening of the shed involves a. rotary advance and each closing of the shed a. rotary compensating recession of the let-oil means, so that said means is constantly oscillating. Again, since adhesion as between the beam and the constricting means is practically eliminated the means to exert constricting pressure on the strain on the material being delivered is beam held against rotation therewith and greatly reduced and its. elasticity is preincluding a flexibly connected system of served. bolsters embracing the beam, and rolling Having thusfully described my invention, pressuretransmitting intermediaries inter- 15 what I claim as new and desire to secure by posed relatively between the holsters and. Letters Patent is: the beam.

In combination, a supporting structure, a In testimony whereof I afiix my signature. beam j ournaled therein and adapted to have 19 the material to be delivered wound thereon, ERNEST BARBER. 

